Female sex and autoimmune conditions
Dr. O’Donoghue: We know that POTS seems to disproportionately affect women. Is that understood? Is it thought that that’s related to the perhaps the autoimmune component of that illness?
Dr. Taub: Yes. The theory is because women tend to have more autoimmune conditions, that’s why they’re more predisposed. There’s a large amount of genetic susceptibility. For instance, we know that there’s an association between POTS and conditions like Ehlers-Danlos syndrome and between POTS and mast cell activation. Some of those conditions are more prevalent in women as well.
Dr. O’Donoghue: I feel like many physicians don’t know how to manage POTS, and they’re actually a little fearful perhaps to take it on. Fortunately, there have been a growing number of POTS clinics with specialists that focus on that area. For the average practitioner who maybe can’t refer to a POTS clinic, how should they approach that?
Dr. Taub: The first thing is its diagnosis. When someone tells you that they have symptoms of orthostatic intolerance – so, activities that involve standing – you need to first have that on your differential diagnosis. You can make the diagnosis in the office with orthostats. You don’t need a tilt table. It’s sometimes helpful if you’re unsure about the diagnosis, but you can make the diagnosis.
Many times, you’re finding people that have very mild symptoms. You can treat that with some good lifestyle recommendations, such as increased hydration, increasing salt in their diet, and compression. And the exercise component is really important.
Many people with POTS are told to go exercise, go for a run, or go for a walk. That’s incorrect, because these people have symptoms when they’re in the upright position. The type of exercise they need to do initially is exercise in the lying or seated position – so exercises like rowing or a seated bike, and strength training. As they start to feel better, then they can do upright exercise.
You should never tell a person that has POTS to just initially start with upright exercise, because they’re going to feel so much worse and then they’re never going to want to exercise. It’s really important to give them the right exercise recommendations. I find that for many of these mild cases, if they do the right exercise and engage in the right lifestyle strategies, they get better.
Compression wear and drug therapy
Dr. O’Donoghue: When it comes to compression stockings, do you usually start with a particular length?
Dr. Taub: It’s interesting. There are many different compression stockings, medical grade. Through patients with POTS, I’ve gotten feedback on certain types of athletic wear that have built-in compression, and that’s a little bit easier for people to wear every day because they can do their errands and it doesn’t look like they’re wearing medical-grade compression stockings.
Basically, I’ve collected all the different recommendations that patients say help, and I give them a list. The medical-grade compression stockings sometimes are very challenging to put on, and sometimes people just need light compression or even just socks. Any kind of compression is going to help.
Dr. O’Donoghue: That’s a great tip, because I know there are many patients who refuse to wear the compression stockings. If there’s a fashionable alternative, that’s always good to reach for.
Dr. Taub: Another thing that patients have told me is that abdominal compression is also very helpful. There are many commercially available abdominal compression options, like shapewear. Many patients with POTS use that and that helps, too.
Dr. O’Donoghue: Good. For those patients with POTS that is refractory to the measures you’ve already discussed, what are the next steps after that?
Dr. Taub: Pharmacotherapy is very synergistic with lifestyle, and there are many different pharmacotherapy options. One of the first things that you want to think about is lowering that heart rate. The reason people feel horrible is because their heart rate is usually very high when they’re upright. If they’re upright for long periods of time and they’re having very high heart rates, they’re going to get really tired because it’s like they’re exercising for hours when they’re upright.
Heart rate lowering is the cornerstone of therapy. Traditionally, we’ve used beta-blockers for heart rate lowering. The problem is they also lower blood pressure. They can also cause fatigue, so not the ideal agent for patients with POTS.
One of the clinical trials that I led was with a drug called ivabradine, which selectively works on the SA node and decreases heart rate without affecting blood pressure. What’s really elegant about ivabradine is it has a more potent effect when the heart rate is higher. When the patient is standing, it’s going to have a more potent effect on heart rate lowering. It’s really well tolerated in patients with POTS. In our study, we showed an improvement in quality of life metrics. That’s one of the first-line drugs that I use for patients with POTS.
The other thing is some of them will also have a concomitant lowering of blood pressure. You can think about medications that increase blood pressure, like midodrine, fludrocortisone, and droxidopa. Sometimes that combination of a heart rate-lowering medication and a medication that increases blood pressure really works well.
Dr. O’Donoghue: That’s very helpful. I think that those kinds of practical tips are the ones that practitioners really want to reach for, because they need to have that algorithm in their mind to take on this condition. Thanks again for walking us through that.
I think it’s a very interesting space, and there’s more that we’re going to be learning over the next few years as we further flesh out these post-COVID cases and what we learn from that as well.
Dr. Taub: There are many clinical trials now starting in POTS, so it’s exciting.
Dr. O’Donoghue: Absolutely. Thank you again for joining me today. Signing off, this is Dr Michelle O’Donoghue.
Dr. O’Donoghue is a cardiologist at Brigham and Women’s Hospital and senior investigator with the TIMI Study Group. A strong believer in evidence-based medicine, she relishes discussions about the published literature. A native Canadian, Dr. O’Donoghue loves spending time outdoors with her family but admits with shame that she’s never strapped on hockey skates. She disclosed ties with Amgen, AstraZeneca Pharmaceuticals LP, CVS Minute Clinic, Eisai, GlaxoSmithKline, Janssen Pharmaceuticals, Merck, Novartis, and The Medicines Company. Dr. Taub is professor of Medicine, University of California San Diego Health, La Jolla. She disclosed ties with Amgen, Bayer, Boehringer Ingelheim, Medtronic, Merck, Novartis, Novo Nordisk, and Sanofi.
A version of this article appeared on Medscape.com.